Thermal energy responsive indicating device



Dec. 30, 1941. G. E. BARNHA'RT 2,268,469

THERMAL ENERGY RESPONSIVE INDICATING DEVICE Filed Feb. 12, 1940 Patented Dec. 30, 1941 UNITED STATES PATENT OFFICE THERMAL ENERGY RESPONSIVE INDICATING DEVICE 4 Claims.

'I'his invention relates to indicating instruments.

The general object of the invention is to provide a novel indicating instrument which is subject to radiation.

A more specific object of the invention is to provide an indicating apparatus which is sensitive to luminous radiation.

An additional object of my invention is to pijovide a' novel indicating instrument involving a pair of hollow expansion members which may be of unequal volume and wherein the contained gas may be of tive members and wherein the movement of an indicator is subject to the combined effect of the two members.

Another object of my invention is to provide an indicator including operating expansion and contraction members so constructed that they are not subject to atmospheric or barometric changes.

Another object of the invention is to provide an indicating device which is sensitive to heat radiation.

A further object of the invention is to provide a novel indicating device which is operated by' an expansion and contraction member.

Another object of the invention is to provide a novel pointer adjusting arrangement for an` indicating device.

Another object of the invention is to provide an instrument including expansible and contractable members, whose movement is eected by forces supplied by members connected-thereto.

Other objects and the advantages of this invention will be apparent from the following description taken in connection with the accompanying drawing, wherein:

Fig. 1 is a side elevation, partly in section, showing an apparatus embodying the features of my invention;

s. 2, 3 and 4 are sections taken on lines 2-2, 2-4, and 4-4, respectively, Fig. 1;

Fig. is a fragmentary enlarged sectional detail Fis. 6 is a section F18. 7 is a section and Fig. 8 is a central sectional view through a casing showing my invention in elevation therein.

Referring to the drawing by`reference chartaken on line B-6, Fig. 5; taken on line 1-1, Fig. 1;

`aciers the invention is shown as embodied in an instrument which is As shown the which a casing indicated generally at Iii. instrument includes a base Ii on l2 is mounted. This casing is diierent pressures in the respec- (Cl. 'i3-151) shown as including a bottom i3 and a transparent top portion I4 hermetically sealed to the bottom.

The bottom i3 includes a recess which receives a cushion member l5 on which a base I6 having a peripheral ilange I1 is mounted.

Mounted on the base I6 I show an inverted U- shaped support I8 which is provided with ieet I9 and stiiening ribs 2U.

'I'he support includes opposed bosses 2l which are aligned and are provided with aligned apertures 22.

Mounted in each of the apertures I show an inlet tube 23 of a bellows member 24. The bellows members are each preferably of the same capacity.

As shown each bellows includes an ear 25 which supports a. pin 2B iitted in a slot 21 in a member 28 which connects the bellows. Each pin 26 is threaded to receive a thumb nut 29, and the construction is such that when the thumb nuts are tightened the bellows are connected by the member 28 to move in unison, and when one of the thumb nuts is loosened the connecting member 28 will be moved by its engagement with the other bellows.

The connecting member 28 includes a pin lll which projects from both sides thereof and is received infslots 3| mounted in the upper portion 32 of a pointer member indicated generally at 33. The pointer 33 includes an arrow 34 movable over a scale 25 on a scale member 36 which includes adjusting slots 31 in a flange 38 thereon. The slots 81 receive bolts 89 which pass 35 through the base Ii and are held in place by thumb nuts so that the position of the scale can be adjusted.

The support i8 includes an arm 4I enlarged at its lower end and recessed at 42. In each recess 40 I arrange a plate 43. The plates 43 as well as the arm are provided with aligned slots 44. The portion 32 of the pointer includes aligned apertures with a collar 46 disposed in one of the apertures and with a fastening member 41 pass- 45 ing through the pointer and through the slots 44 in the arm 4i and in the plates 4I.

The fastening member 4'I at lone end includes a head 48 and at the other end a thumb nut 49 and the construction is such that by loosening the 5o thumb nut 48 the position of the upper end of the pointer on the arm 4| can be adjusted.

Mounted on each of the inlet tubes 23 I show a. tube 5l of a bulb member 5I which affords communication between each bellows and its associated bulb. A suitable sealing means 52 insures a tight joint. This sealing means 52 is arranged in an enlarged portion 52 on the tube 50.

Each of the bulbs 5l as shown includes an insulating jacket 53 with the space between the bulb and jacket preferably exhausted. 'I'he bulbs 5I are preferably of dierent volumes and as shown each bulb contains a heat absorbing disk 55 notched at 56 to permit gas flow from the bulb to its associated tube. The bulbs when of diierent volumes and with a heat absorbing disk in each bulb, provide a differential eil'ect, thereby increasing the sensitivity and accuracy of the dev ice.

The disk 55 may be black or of any color depending on the intended use oi' the instrument and the bulbs may be filled with gas such as nitrogen which communicates with the interior oi the bellows.

The device may be used as shown in Fig. 1 or in certain instances 'it may be placed in a casing as shown in Fig. 8.

In use the needle member 33 is adjusted so that it hangs in a vertical position andthe scale 35 is adjusted so that the zero thereon is in line with the end of the pointer.

The bulbs are then subjected to the type of radiation the effect of which is to be determined and a reading is taken. The scale may be suitably calibrated with a known standard or the reading may be made with two or more intensi- Lies of radiation, one of which is of standard character so that the effect produced on the instrument can be determined.

It will be apparent that one of the bulbs 5I may be omitted in certain types, and that for certain purposes one or both of the heat insulating 4jackets may be omitted. It will also be understood that the term bellows used herein may be construed as referring to hollow multiple diaphragms, Bourdon tubes and other expansion and contraction members and that suitable means for controlling the volume of the expansible members during the manufacture of rthe instrument may be employed.

In certain instances the disks maybe entirely omitted and in other instances the color of the disks may be varied and that the disclosure is by way of illustration only and that various changes can be made within the terms of the claims. A

Having thus described my invention, I claim:

1. In an instrument of the class described, va

a support on said base, a pair of expansion and contraction members mountedlon said support, each of said members including an inlet tube at one end, means connecting the inner ends of said expansion and contraction membulbs having a heat absorbing plate therein, the plates in the two bulbs being substantially coplanar, a pointer, and means operated by said connecting means for shifting the pointer.

2. In an instrument of the class described, a base, an inverted U-shaped support on said base, said support including aligned apertures, a pair of expansion and contraction members, each of said members including an inlet tube arranged in one of said apertures and projecting outwardly beyond the end thereof, means connecting the pansion and contraction members, each inner ends of said expansion and contraction members, an indicator, means operated by said connecting means for shifting the indicator, a pair of bulb tubes each mounted on one of said member tubes, said bulb tubes being aligned with said member tubes, a bulb mounted on each of said bulb tubes, a vertically disposed heat absorbing plate withinfeach of said bulbs, the plates in the two bulbs being coplanar and having notches to permit gas to flow from both sides of the plate in each bulb to its associated tube, one of said plates being of greater area than the area of the other plate.

3. In an instrument of the class described, a.

base, an inverted U-shaped support on said base, said support including aligned opposed apertured bosses, a pair of expansion and contraction members, each of said members including an inlet tube arranged in one of said apertures and projecting outwardly beyond the end thereof, means connecting the inner ends of said expansion and contraction members, an indicator, means operated by said' connecting means `for shifting the indicator, a pair of bulb tubes each having an enlarged end recess with a gasket therein, one of said gaskets being fitted on one of said member tubes, the other gasket being fitted on the other` member tube, said bulb tubes being aligned with said member tubes, a bulb mounted on each of said bulb tubes, a vertically disposed heat absorbing plate within each of said bulbs, said plates associated bulb through its center, the plates in the two bulbs being coplanar the axis of all of said tubes, each of said plates being notched adjacent the bulb tube to permit gas to iiow from both sides of the plate in each bulb to its associated tube.

4. In an instrument of the class described, a base, an inverted U -shaped support on said base, strengthening ribs connecting said base and the sides of said support, said support including alined opposed apertured bosses, a pair of exof saidv members including an inlet tube arranged in one of said apertures and projecting outwardly beyond the end thereof, means connecting the inner ends of said expansion and contraction members, an indicator, means operated by said connecting means for shifting the indicator, a pair of bulb tubes each having an enlarged end recess with a `gasket therein, one of said gaskets being tted on one of said member tubes, the other gasket being itted o'n the other member tube, said bulb tubes being axially aligned with said tubes, each of said plates being notched adjacent the bulb tube to permit gas to flow from both sides of' the plate in each bulb to its associated tube, one of said bulbs and its associated plate GEORGE E. BARNHART.

and intersecting 

